This look - especially considering the basket hilt sword - is appropriate for 1590's (just barely!) thru 1746. Of course the 3-drone pipes are a later development ....
Ren Fairs are not places to worry about what is or is not period.
Thank you for the history lesson. I personally don't care to go about barefoot in a léine & tartaine, and according to Joseph MacDonald's "Compleat Theory of the Scots Highland Bagpipe", by 1760 the three drone configuration of a bass and two tenor drones was sufficiently well established to be considered representative of the type. It's certainly been my experience that when someone hires a piper, they expect a kilt; I doubt I'd get nearly as many gigs wearing something that looks like a maiden's shift and a horse blanket, and I'd certainly hate to dissapoint my creditors. Besides, I seriously doubt that my wife (or other clients) would go for the long hair, long beard, and long term lack of personal hygeine true period authenticity would require...and then there are my failings in archaic Gaelic and piobaireachd...but hey; all life involves compromise.

Illustration from MacDonald, c. 1762